Thermopiles


haarp.GIF
Thermopile supporting an antenna tower at the HAARP facility at Gakona, Alaska

Thermopiles are load bearing two-phase thermosyphons that are generally used to found structures where permafrost soils exist. Typical thermopile applications follow:

  • Installation at sites with a frost-susceptible active layer where heave and pile jacking are problems. Thermo-cycling reduces frost heave forces to negligible quantities.
  • Installation in marginal permafrost where pile creep rates are high. Thermo-cycling reduces soil temperatures and subsequently reduces creep rate.
  • Installation at sites with saline permafrost where allowable stresses are reduced due to substantial quantiies of unfrozen water in the soil matrix. Thermo-cycling freezes water near piles and pushes salts away. Also proven effective for moving glycol from a piling face.
  • Installation at sites where development has increased the heat load to the subgrade. Heat transfer rates of the Thermopiles need to be sized to balance or exceed heat load.